Hi to all:


With regards to analysis of FRP piping in CAESAR II, what the necessary items to be set-up in the configuration. Since, I'm new in this type of piping in analysis, any suggestion with regards to this matter is highly appreciated.


Thank You!

Do you have specific questions on these fields that the "help" didn't answer?

The question is why the stress reports ratios to the allowable in FRP OPE case but reports zero in steel pipe OPE case. I will appreciate if you could give me a clue. Does CAESAR has a manu addressing FRP piping calculation?

Dear Mr.Ay,



Since I am new i FRP piping my answer is YES, HELP menu for FRP not clear for me.

With regards to this matter, we use the B31.3 code.

Please correct me if I'm mistake, in FRP piping I consider pressure expansion, it is ok to set the "PRESSURE VARIATION IN EXP CASE" to YES not to DEFAULT set-up in the configuration file. To add any query, what are the necessary items to set-up in CONFIGURATION file in doing the analysis for FRP piping.

For example, some data from the vendor of FRP piping:

Hoop = 210Mpa
Axial = 75 Mpa
Hoop/Axial = 2.8

Static HDB = 148 Mpa
Yield HDS = 74 Mpa


Some item stated above(corect if I'm mistake) static HDB which is 148Mpa is an allowable stress which is inputed in the CAESAR II spreadsheet allowable menu & yield HDS which is 74 Mpa is the yield stress also.


THANK YOU & MORE POWER!

@HenryQ: You've also asked that question here: http://65.57.255.42/ubbthreads/ubbthreads.php?ubb=showflat&Number=38273#Post38273
and I think I have answered that already. Study material behaviour and the applicable piping codes! Let me give you an extra clue: Does FRP have elestic-plastic behaviour like steel does?

@machoguy: First of all you're not using the best code for FRP analysis. See my answer to HenryQ above and all other topics in this forum related to FRP stress in OPE case. It has been asked and answered numerous times.

In the config there are a couple of settings regarding FRP. Thermal expansion coefficient is the most important one. A second one is the FRP config file, but that file is not important as you can enter the material properties in the normal input on the first element. And you can enter the type of laminate used for tees and such, but this can be important depending on the code, but not important in general.

What is important for FRP piping:
- setting the expansion coefficient in the config
- using the correct piping code (UKOOA, BS7159, ISO14692)
- using the correct material properties (check the code what to use).

Most important:
- read up on FRP material properties and properties definitions.
- read up on FRP piping codes.

@corne B31.3 can be used with its limitations (please see Chapter VII)
For example Smith Fibercast can provide guidance on this.
Sometimes client will force you to provide calculations using B31.3 and manufacturer requirements.
Best regards,

HenryQ -

In a flexibility analysis steel pipe is assumed to have certain failure modes which are addressed by the Sustained, Expansion, and sometimes the Occasional load cases. The Operating condition does not address these modes of failure and there for is not a "stress compliance case", hence CAESAR II sets the allowable stress values to zero. See this previous post, which is a "sticky topic" at the top of this forum for additional details.

With FRP systems however, the failure mode is completely different - there is no allowable stress value. Rather there is a failure envelope to be evaluated. This is discussed in detail in Chapter 6 of the CAESAR II Technical Reference Manual.

Hi Richard,

Thank you very much for the answer. I like your answer because it is always exactly I wanted, not too little or too much.
Thank you corne as well.